Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The annotations already declare readOnlyHint=true, and the description's informational content is consistent with that. The description adds context that the tool explains buying mechanics and is a prerequisite for first-time shop interactions, which goes beyond the annotation. However, it doesn't disclose return format or edge cases, but with annotations present this is acceptable.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, well-structured sentence that front-loads the key information (what the tool reveals) and ends with a clear usage directive. No wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a parameterless read-only info tool, the description covers the essential information: purpose, content, and when to call. The sibling tools and annotations provide additional context, and no output schema is needed. The description is sufficient for an agent to select and invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has zero parameters, and the schema description coverage is 100% trivially. The description correctly doesn't attempt to explain parameters. According to the rubric, a 0-param tool gets a baseline of 4, and there is no reason to deduct.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool provides shop-level information: what the shop sells, pricing, and purchasing process. This distinguishes it from sibling tools like list_products, which would focus on individual products, and order-related tools. The verb 'get' is implied by the name and the description gives specific content categories.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly says 'Call this first if you have not dealt with this shop before,' providing clear when-to-use guidance. It does not mention alternatives or when-not-to-use, but the directive is strong and sufficient for most cases.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.